A suicide bomber targeting a microbus in Kabul on Tuesday left at least 12 people dead, eight of which are believed to be foreign civilians predominately from South Africa.

A female bomber detonated a car packed with explosives near the microbus at approximately 6:30 a.m. as the victims were reportedly going to the airport. The bomb also caused significant damage to a nearby wedding hall.

Hizb-e-Islami, an insurgent group that has traditionally been among the more moderate organizations in Afghanistan, claimed responsibility for the attack, saying it was in retaliation for the anti-Islam film trailer on YouTube that sparked demonstrations throughout the Middle East and Africa.

“In the operation in reaction to the disrespect of the holy prophet, 16 American spies were killed today in Kabul,” said the group in an official statement. Insurgent groups often overestimate the death toll of such attacks and misstate the nationality and profession of those killed.

Reaction across Afghanistan to the anti-Islam video has been relatively muted so far with only one major demonstration on Monday, at which hundreds of Afghan protesters threw large stones at the Afghan police.

Tuesday’s attack, especially coming from a moderate insurgent group known for its willingness to talk to international forces and officials in Afghanistan, may indicate mounting anger with foreigners in Afghanistan.

This growing frustration is likely to challenge the US and NATO, who just announced that they’ve severely restricted partnered operations with Afghan forces in response to fallout from the video and from an increase in Afghan security forces killing international soldiers.

“Suicide bombings are an unusual thing for Hizb-e-Islami. They’ve never conducted such an attack that I can remember, and they weren’t showing a lot of interest in suicide attacks before this,” says Haji Saleh Mohammad, a member of parliament who sits on the security commission. “There is concern that attacks against individual military personnel or nonmilitary foreigners will start here in the city, because if the foreigners continue making issues about the Quran and Muslims such as this film did, it definitely causes hatred.”

Hizb-e-Islami is a significant group within Afghanistan, but it does not have the same level of influence as other groups such as the Taliban or the Haqqani Network. An active opponent of international and Afghan forces here, the group maintains a much more liberal stance on many issues compared to other groups.

In the past, it’s publicly supported girls’ education, criticized insurgent groups who attack reconstruction projects, offered to protect a critical gas pipeline project, and asked its militants not to use roadside bombs because they frequently result in civilian casualties.

“This is not the first time we carried out suicide attacks,” says Zubair Sadeqi, a spokesman for Hizb-e-Islami’s military wing. “We don’t do a lot of suicide attacks, but when it becomes a religious issue we are ready to carry out suicide attacks.”

The group has also been among the most willing to speak with international forces looking for a negotiated settlement to end to conflict here at a time when foreign officials have struggled to make inroads with the Taliban and other organizations. Still, says Mr. Sadeqi, the latest bombing is not necessarily an indication that the group will stop talks with international forces. Such decisions, he says, will be left to the group’s political wing.

Many Afghans say that anger stemming from incidents like the release of the anti-Islamic YouTube video tend to be short-lived and Afghans generally return to the status quo within a matter of days.

“Every Afghan knows that the presence of foreigners is useful to this country,” says Ahmad Zia Rafat, an independent political analyst in Kabul. “Hizb-e-Islami and the Taliban will continue these kinds of attacks as much as they want, but the people, especially those in the cities, will not try to harm foreigners.”